Story highlights

Trump praised the policing practiced under former New York City Mayor Rudy Giuliani

He also seized on the unrest to appeal to African-Americans to join his campaign

Pittsburgh (CNN)Donald Trump called Thursday for a "national anti-crime agenda" to combat violent crime in US cities as he condemned the unrest that unfolded overnight in Charlotte, North Carolina, where protests turned violent.

"Our country looks bad to the world, especially when we are supposed to be the world's leader. How can we lead when we can't even control our own cities," Trump said during a speech here to a conference of shale oil and natural gas producers.

After police shot a man officials say was armed, two nights of protests followed there, slipping into violence Wednesday night with numerous civilian and police injuries reported, as well as looting and property destruction.

Trump, who has focused on restoring "law and order" in his presidential campaign, seized on the unrest in Charlotte to renew his call for tough-on-crime policies to bring down crime rates in major American cities and once again appeal to African-Americans to join his campaign.

"The people who will suffer the most as a result of these riots are law-abiding African-American residents who live in these communities where crime is so rampant," Trump said. "There is no compassion in tolerating lawless conduct. Crime and violence is an attack on the poor and will never be accepted in a Trump administration, ever, ever."

Trump also tied the eruption of violent protests on Wednesday night to drugs, saying in Pittsburgh that "drugs are a very, very big factor in what you're watching on television at night" -- though he offered no evidence to back up that claim.

Steven Cheung, a Trump campaign spokesman, later said it was "obvious" Trump was "referring to the recent increase in drug related deaths and subsequent news reports, thus making it a hot button issue."

Praised stop-and-frisk

Trump praised the policing practiced under former New York City Mayor Rudy Giuliani, which included the use of "stop-and-frisk" and a greater crackdown on misdemeanor offenses and has been credited with helping bring down the city's crime rate during the 1990s.

"Think of how many families these policies saved from the worst heartache possible," Trump said of Giuliani, who is now a top adviser and surrogate.

During that interview, Trump also highlighted what he saw as a "lack of spirit" between communities.

"It just seems that there's a lack of spirit between the white and the black. I mean, it's a terrible thing that we're witnessing," he said.

Trump offered few details in his Pittsburgh speech of what would be included in his "national anti-crime agenda to make our cities safe again," beyond saying that he will "make reduction of crime a top priority" and appoint "the best" prosecutors and federal investigators to go after criminal gangs and cartels.

Trump has previously said that he would look to increase the number of police officers in inner cities to bring down the crime rate and improve training, but has offered little other specifics on this policy front.

"Safety is the foundation of the ladder to American success," he said.